group implicated high theta coherence as most significant for alcohol dependence in a sample of non-COGA participants as well as for significant genetic association in a COGA sample of linkage families, densely affected with alcohol dependence9, whereas the current study’s findings focus on genetic associations with low theta (3-5 Hz) coherence with alcohol use behavior. As noted above, while low and high theta are highly correlated, there is evidence of distinctions between the two sub-frequency bands. While both the prior and current genetic samples were derived from COGA, the current analytic sample differs from the previous analytic sample in several important ways that may impact the association of low and high theta with alcohol use behavior. For example, the previous genetic study was limited to participants of European ancestry, and had larger proportions of males, older individuals, and subjects more severely affected with AUD. The current sample also includes participants of African ancestry, more females and younger individuals, and those less severely affected with AUD. Given research indicating that ancestry72, sex73, age74,75 and disorder severity76 each introduce important heterogeneity in genetic association findings of complex traits, as well as in the EEG parameters themselves77-80, it is highly plausible that findings
